int buf_sz = rados_pool_list(clu,NULL,0);
  char buf[buf_sz];

[download]

With some compilers, that won't assign buf_sz chars to buf. I would expect that, on such compilers, that piece of code would cause an error - and the module would not compile.
However, if it didn't throw a compile-time exception, then you would most likely experience a runtime segfault.

It's safer, IMO, to assign the memory dynamically - something like (UNTESTED): 

use Inline C => Config =>
 BUILD_NOISY => 1;

__C__
void list_pools_c (rados_t clu) {
  Inline_Stack_Vars;
  int buf_sz = rados_pool_list(clu,NULL,0);
  char *b;
  int r;

  Newx(b, buf_sz, char);

  r = rados_pool_list(clu,b,buf_sz);

  if (r != buf_sz) {
    printf("buffer size mismatch: got %d the first time, but %d "
    "the second.\n", buf_sz, r);
  }

  Inline_Stack_Reset;

  while(1) {
    if(b[0] == '\0') {
      Inline_Stack_Done;
      Safefree(b);
      break;
    }
    Inline_Stack_Push(sv_2mortal(newSVpv(b,0)));
    b += strlen(b) +1;
  }
}

[download]
I've moved the Inline_Stack_Vars to the top as is my usual practice - though I don't think that matters here.
And I've also added the BUILD_NOISY option so that any warnings from the compilation of the C code can be seen. (FAIK, the module might already have turned BUILD_NOISY on, in which case my re-iteration of it can be removed.)
Not sure if any of that will help - if it doesn't you could try inserting printf("Got to A\n"); statements into the C code in order to locate the segfault more precisely.

Cheers,
Rob

In reply to Re: [Ceph::RADOS] Help Debugging Inline C by syphilis
in thread [Ceph::RADOS] Help Debugging Inline C by three18ti

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